As used herein, “intangible goods” is a generic label for electronically stored or transmitted content. Examples of intangible goods include images, audio clips, video, multimedia, software, metadata, and data. An intangible good may be analog or digital. Depending upon the context, an intangible goods may also be called a “digital signal,” “content signal,” “digital bitstream,” “media signal,” “digital object,” “object,” and the like.
Intangible goods are often distributed to consumers over private and public networks—such as Intranets and the Internet. In addition, these goods are distributed to consumers via fixed computer-readable media, such as a compact disc (CD-ROM), digital versatile disc (DVD), soft magnetic diskette, hard magnetic disk (e.g., a preloaded hard drive), portable media players, and flash memory cards. Furthermore, goods are distributed via communications streams such as those originating from a client such as an instant messenger or another audio/visual chat application.
Unfortunately, it is relatively easy for a person to pirate the content of intangible goods at the expense and harm of the content owners—which include the content author, publisher, developer, distributor, etc. The content-based industries (e.g., entertainment, software, audio and/or video, film, etc.) that produce and distribute content are plagued by lost revenues due to piracy.
Embedded-Signals
Embedding one or more signals in a carrier signal (e.g., intangible goods) is one of the most promising techniques for protecting the content owner's rights of intangible goods. This embedded-signal is commonly called a “watermark” and the embedding process is commonly called “watermarking.”
Generally, watermarking is a process of altering the intangible good such that its perceptual characteristics are preserved. For example, a “watermark” is a pattern of bits or signal stream inserted into a digital or analog good that may be used for many purposes, such as identifying the content owners and/or the protected rights.
A watermark embedder (i.e., encoder) is used to embed a watermark into intangible goods. A watermark detector is used to detect the existence of the watermark in the watermarked intangible goods and possibly identifying that watermark.
Watermark detection is often performed in real-time even on small electronic components. Such a “real-time” detector is also often called a “dynamic detector.” Generally, this means that the detector is attempting to detect a watermark in intangible goods as the goods are being consumed (e.g., played, presented, stored, and such). For example, if the intangible good is an audio signal, the detector attempts detection while the audio signal is being played.
Such dynamic watermark detection is often a very expensive operation (in terms of computing resources). If there are multiple input streams, then conventionally there are multiple dynamic watermark detection modules running (i.e. one per input stream). The expense in computing resources increases with each watermark detection module invoked to operate on an input stream.
Those of ordinary skill in the art are familiar with conventional techniques and technology associated with watermarks, watermark embedding, and watermark detecting.